Summary: | 碩士 === 國立高雄科技大學 === 機械與自動化工程系 === 107 === The lightweight and precision of locomotive parts has been the development direction of the manufacture of locomotive parts in recent years. The former can reduce energy consumption and meet current environmental claims, while the latter can reduce production costs. Under this demand, in recent years, the manufacture of locomotive drive shafts has been innovated by the hollow cold forging precision forging process.
In the past, such shaft-shaped products were forged by the traditional hot burr forging, the material was transversely forged, and the burrs were removed, and then mechanically processed. Due to the lightweight consideration, the middle hole was processed by deep hole drilling. Therefore, the traditional hot forging process, due to the burr design, the material utilization rate is low, about 65%; the forging is rough, the machining volume is large; in addition, the medium hole processing cost is high, and the deeper the hole depth, the processing cost increases.
In this study, SCM420H low-alloy steel was selected as the material, and the material was spheroidally annealed to below 78HRB. The feasibility of the five-station mold design was analyzed using DEFORM simulation software, and the mold design of the shaping process and the extrusion hole punch was discussed. And the overall mold design.
According to the simulation results, the mold parts are designed and the forging experiment is carried out. The discussion focuses on whether the quality of the mesoporous section and the depth of the mesopores and the fifth pass shaping process can be achieved. When the medium hole forgings are extruded through experiments, materials can be found. The difference in the influence of the annealing process on the mesoporous cross section. When the fourth and fifth processes are to be carried out later, the depth of the punch is deeper due to the deeper the length of the punch. Therefore, from the integrated punch to the vertical inner punch and the outer punch base, the size of the forged piece can be entered into the tolerance and stabilized, and the mold operates smoothly, which proves that the forging process is feasible.
This study successfully established The Study on Development of the Application Cold Hollow Forging Process, with the first pass 1.67, the second pass 3.4, the third pass 5.17, the fourth pass 6.9 aspect ratio punch, and the use of materials. The rate saves 16% of the material, and successfully squeezes the hole and material length at the same time, so that each workpiece has less processing cost of deep hole drilling of more than 100 yuan and processing time can save 100 seconds, for production efficiency and cost.
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